The goals of this projects are: 1. to use a set of tasks in which both behavior and cortical event-related potentials (ERPs) are recorded to assess age-related changes in specific aspects of perceptual, cognitive, and motor functioning; and 2. to use these or similar tasks to evaluate the effectiveness of an ergot alkaloid, dihydroergotoxin mesylate (DEM, Hydergine), in a group of elderly subjects. In the first phase of the project, normal controls aged 20-30 (N equals 16) and subjects over 60 years of age with various degrees of behavioral impairment (N equals 32) will be given a set of tasks designed to assess both the speed and accuracy of specific perceptual, cognitive, and motor functions associated with the processing of verbal and non-verbal materials; behavior and ERPs recorded in these tasks will allow a specification of differences in CNS functioning between and within these groups. In the second phase of the project, similar tests will be used in a placebo-drug-placebo design to evaluate the effectiveness of DEM in a group of elderly subjects with various degrees of behavioral impairment (N equals 32); this will allow an examination of DEM's effects on specific age-related impairments in CNS funtioning and will allow us to determine whether any specific pattern of CNS impairment characterizes those patients who are most likely to benefit from DEM.